1. Field of the Invention
Embodiments of the present invention relate to a power supply circuit for a gate driver of a floating switch and a gate driver circuit of the floating switch having the same.
2. Discussion of Related Art
A conventional gate driver circuit is configured to provide a unipolar voltage to an upper switch gate driver and a lower switch gate driver to drive all of upper and lower switches.
A unipolar gate driver circuit according to the related art has difficulties including a parasitic current oscillation occurring upon a turn-on operation due to a high slew rate caused by a Miller capacitance of an insulated gate bipolar transistor (IGBT), an unintended turn-on phenomenon due to parasitic components, and the like.
To address such difficulties, a switching mode power supply (SMPS) for applying power supply to a gate driver should provide a wide range of voltages, or an additional circuit should be provided so as to form a negative gate voltage. As a result, power consumption due to the SMPS adopted in the gate driver is increased, a complicated circuit is needed, and a manufacturing cost is increased. Also, a Miller clamp circuit should be added so as to prevent the unintended turn-on phenomenon such that this is another factor to increase the manufacturing cost.